JPH0856571A - Oil-in-water type emulsion - Google Patents

Abstract

PURPOSE: To obtain an oil-in-water type emulsion, having a relatively high viscosity even without using a thickener such as gums or starch, further good shape retaining properties and high emulsification stability even in preservation especially at high temperatures. CONSTITUTION: This oil-in-water type emulsion comprises 90-40wt.% aqueous phase and 10-60wt.% oily phase. The aqueous phase contains at least one or more proteins selected from the group consisting of egg proteins, soybean proteins, milk proteins and simple proteins separated from the proteins in an amount of 0.3-3wt.% expressed in terms of solid content. Oil droplets, emulsified and dispersed in the aqueous phase have 1.0-4μm average particle diameter.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to an oil-in-water emulsion. More specifically, the present invention relates to an oil-in-water emulsion that can be advantageously used for mayonnaise-like foods, etc., which have good emulsion stability even under high temperature storage.

[0002]

BACKGROUND OF THE INVENTION Oil-in-water emulsified foods such as mayonnaise, dressings, and spreads have generally been prepared by roughly emulsifying (preliminarily emulsifying) an aqueous phase raw material and an oil phase raw material in advance with a mixer such as a mixer. It is manufactured by using an emulsifying machine such as a colloid mill to make oil droplet particles finer to have a particle diameter (average particle diameter of about 2 to 4 μm) that forms a relatively stable emulsion. Since such a food has a high proportion of the oil phase raw material (65% by weight or more), a relatively high viscosity (100,000 centipoise or more at 20 ° C.) is obtained, and for example, the shape of the food even when extruded from a container is high. It has a good shape retention property that is maintained. However, when an emulsion (for example, mayonnaise-like food) is made by reducing the ratio of the oil phase raw material (60% by weight or less), only a product having a relatively low viscosity can be obtained, and therefore the shape retention property is also lowered. , It becomes difficult to obtain a stable emulsion. Therefore, thickeners such as vegetable gums and starch are often used for the purpose of increasing the viscosity of such foods with reduced oil phase raw material and improving the shape retention. However, when such a thickener is used, the obtained oil-in-water emulsified food has a sticky feeling in the mouth when eaten, has a poor mouth-melting property, has a heavy texture, and has a good flavor. There is a problem that it is likely to be accompanied by deterioration (Japanese Patent Laid-Open No. 3-91460).

In order to improve texture and maintain viscosity and shape retention without using the above-mentioned thickener, an oil-in-water emulsion food is produced by using heat-coagulated and refined protein raw material. A method (Japanese Unexamined Patent Publication No. 58-23764), a method of producing an oil-in-water emulsified food by emulsifying a whey protein concentrated purified product, and manufacturing it (Japanese Unexamined Patent Publication No. Sho 63-181972) have been proposed. However, in these methods, heat treatment is required to obtain a product, and although the viscosity and shape retention are improved, the heat treatment tends to impair the flavor of the protein raw material, and thus the flavor of the product.

[0004]

DISCLOSURE OF THE INVENTION The present inventors have examined the emulsified state of an emulsion having a composition in which the ratio of the oil phase raw material is reduced as described above. According to it, when the preparation of an emulsion having a reduced proportion of the oil phase raw material using an emulsifying machine such as the colloid mill, the average particle size of the oil droplets is:
It was found that the ratio becomes relatively large (6 μm or more) as compared with the case where the ratio of the oil phase raw material is high as described above, and thus it is difficult to obtain sufficient emulsion stability. And especially under high temperature (2
It was found that the emulsion stability was significantly deteriorated during storage at 5 ° C. or higher), and as a result, part of the emulsion might be separated.

Therefore, an object of the present invention is to have a relatively high viscosity without using a thickening agent such as gum and starch, and to have a good shape-retaining property, and especially during storage at high temperature. An object of the present invention is to provide an oil-in-water emulsion having high emulsion stability. It is also an object of the present invention to provide an oil-in-water emulsion suitable for the preparation of an emulsified food with relatively little deterioration in flavor, texture and the like.

[0006]

As a result of the subsequent research conducted by the present inventor, it was found that a specific protein was used in a specific amount in an aqueous phase for an emulsion having a composition in which the proportion of the oil phase raw material was reduced. By setting the average particle size of the oil droplet particles dispersed in 1 to 4 μm, it has the same viscosity and shape retention as an emulsion with a high proportion of the oil phase raw material, and the flavor, texture, etc. are also impaired. The present invention has been completed by finding that a stable emulsion can be obtained even under high-temperature storage without being treated. In addition,
The increase in viscosity to the extent that the mayonnaise-like shape retention of the resulting emulsion is maintained occurs near the isoelectric point of the protein containing the pH on the aqueous phase side of the emulsion. In the environment, it is considered to be due to the strong interaction between the protein and the oil droplet.

The applicant of the present invention has found that the oil-in-water emulsified product has a good shape retention property without using a thickening agent such as gum and starch, and has an improved texture and flavor. Have been proposed (JP-A-6-54662). This emulsion contains 1 to 10% by weight of a specific protein in terms of solid content, and is prepared such that 80% or more of the oil droplets emulsified and dispersed in the aqueous phase have a particle size of 1 μm or less. However, in terms of emulsion stability (especially emulsion stability under high temperature storage), the emulsion of the present invention is more favorable.

The present invention comprises 90-40% by weight of an aqueous phase and 1
An oil-in-water emulsion comprising 0 to 60% by weight of an oil phase, wherein the water phase has a solid content of 0.3 to (as an absolute dry matter).
An oil containing 3% by weight of at least one protein selected from the group consisting of egg protein, soybean protein, milk protein and a single protein separated from these proteins, and emulsified and dispersed in the aqueous phase. The oil-in-water emulsion is characterized in that the drops have an average particle size of 1.0 to 4 μm.

The present invention preferably has the following aspects. (1) Oil droplets that are emulsified and dispersed in the water phase are 2 μm to 3.
It has an average particle size of 5 μm. (2) The oil-in-water emulsion comprises an aqueous phase of 90 to 50% by weight and an oil phase of 10 to 50% by weight. (3) The aqueous phase has a solid content of 0.
It contains 3 to 2% by weight (more preferably 0.3 to 1% by weight, especially 0.3 to 0.8% by weight) of the above protein. (4) The pH of the aqueous phase is in the range of 3-7.

The oil-in-water emulsion of the present invention will be described below. The oil-in-water emulsion of the present invention comprises 90-40% by weight (preferably 90-50% by weight) of an aqueous phase and 10-6.
It is composed of 0% by weight (preferably 10 to 50% by weight) of the oil phase. The aqueous phase contains at least one protein selected from the group consisting of egg protein, soybean protein, milk protein and a single protein separated from these proteins. The oil droplets emulsified and dispersed in the water phase have an average particle diameter of 1.0 to 4 μm.

The egg protein, soybean protein, milk protein or the single protein separated by these proteins used in the present invention may be any of those which are water-soluble or those which can be solubilized by pretreatment, for example: You can list the following. As egg protein, liquid or dried egg yolk, protein, whole egg and single (simple) separated from these
Proteins such as ovalbumin, conalbumin, ovomucoid, ovoglobulin and the like. Examples of soybean protein include defatted soybean powder, concentrated soybean protein, separated soybean protein, extracted soybean protein, soybean protein obtained from defatted soybean such as dried soybean milk, and single (simple) protein separated from these, such as 7S globulin and 11S. Examples include globulin and 15S globulin. Milk proteins include skim milk powder, whey protein, buttermilk powder and single (simple) proteins separated from them, such as casein, lactoglobulin, lactalbumin, serum albumin and immunoglobulin. Of the above, those suitable for the viscosity and flavor required for the product are appropriately selected alone or in combination. Other proteins, such as animal proteins,
You may use together vegetable protein or the single protein isolate | separated from these.

The above protein is 0.3 to 3% by weight (preferably 0.3) in terms of solid content (as an absolute dry matter) in the aqueous phase.
.About.2 wt%, more preferably 0.3 to 1 wt%, especially 0.3 to 0.8 wt%). If the content of the above-mentioned protein is less than 0.3% by weight, the increase in viscosity is not sufficient, while if it exceeds 3% by weight, the viscosity tends to be high enough to maintain the shape-retaining property, but the storage stability of the emulsion is improved. Is likely to decrease.

The oil droplets emulsified and dispersed in the water phase of the oil-in-water emulsion of the present invention have an average particle diameter of 1 μm to 4 μm (preferably 2 to 3.5 μm) on a volume basis. .

The aqueous phase of the oil-in-water emulsion of the present invention can be arbitrarily constituted depending on the intended product. Examples of the component that constitutes the aqueous phase include water, raw materials in the form of water or an aqueous solution such as vinegar, fruit juice, and milk. Further, the aqueous phase may contain salt, sugar, spices, seasonings, etc., if necessary. On the other hand, the components that make up the oil phase are
Oils and fats may be the main component, and spice oil or the like may be added thereto. The oil and fat may be of any type as long as it is edible. For example, soybean oil, rapeseed oil,
Liquid oils and fats such as corn oil and cottonseed oil are generally used, but solid oils and fats such as palm oil and coconut oil can also be used. Further, those oils and fats may be oils and fats that have been subjected to treatments such as hardening, fractionation and transesterification.

The oil-in-water emulsion of the present invention can be prepared by emulsifying an aqueous phase raw material containing the above protein as a part of the raw material and an oil phase raw material containing edible oil and fat into an oil-in-water type emulsion.
The method is no different from the conventional method except that the oil droplets dispersed in the water phase have the specific particle size distribution as described above. As a means for refining the particle size of the oil droplets to a desired particle size, a conventionally known method can be used. For example, devices such as a mountain gourin, a high-pressure homogenizer such as a microfluidizer, and an ultrasonic emulsifier can be used. And depending on the device used,
The production conditions (temperature, pressure, time, etc.) may be appropriately set and the production may be performed so as to obtain the desired emulsion. In the emulsion prepared by using a fine emulsification means such as a high-pressure homogenizer as described above to have the oil droplet particle size of the present invention, the oil droplets constitute a matrix, and the emulsion having enhanced emulsion stability Becomes Incidentally, also in the preparation of the emulsion of the present invention, glycerin ester, an edible emulsifier such as sugar ester and the like in the same manner as in the conventional method, and in some cases, viscosity, a physical substance gum quality in the range without the influence of the texture, etc., You may mix | blend thickeners, such as starch.

The oil-in-water emulsion of the present invention obtained as described above preferably has a viscosity of 30,000 centipoises (cp) or more and 200,000 centipoises (cp) or less, and more preferably. , 50000
It is in the range of 0 to 150,000 centipoise (cp).

The oil-in-water emulsion of the present invention can be made into various emulsified foods by adjusting the composition. For example, acidic oil-in-water emulsion foods such as mayonnaise-like foods (emulsions obtained by emulsifying an aqueous phase and an oil phase containing an organic acid and / or salts thereof and exhibiting pH 3 to 7) and sand cream There are spreads, etc. In the present invention, a mayonnaise-like food having the following composition is particularly preferable. 10 to 60% by weight of fats and oils, 0.3 to 3% by weight of protein selected from the group consisting of egg protein, soybean protein, milk protein and a single protein separated therefrom (solid content), vinegar 10 to 20% by weight (As 5% acidity vinegar),
Consists of 1 to 3% by weight of salt, 0.5 to 2% by weight of mustard, and water (remaining amount), and if necessary, a small amount of seasoning such as emulsifier, sodium glutamate, and pepper. There is.

[0018]

EXAMPLES The present invention will be described more specifically below with reference to Examples and Comparative Examples. The viscosity of the following emulsion was measured using a B viscometer (B-8H type, manufactured by Tokyo Keiki Co., Ltd.). Performed at 2.5 rpm with 6 rotors. The particle size of oil droplets dispersed in the water phase is measured by a laser diffraction particle size distribution measuring device (SALD-1100 type, Shimadzu Corporation).
Manufactured) was used to process the obtained measured values with a computer and expressed as a volume-based particle size distribution.

Example 1 0.46 parts by weight of egg white powder (0.4% by weight of dry protein solids), 17 parts by weight of vinegar (acidity 5%), 2 parts by weight of salt, 0.4 parts by weight of sodium glutamate, 0.02 parts by weight of mustard and 45.1 of fresh water
An aqueous liquid was prepared by uniformly mixing 2 parts by weight at about 20 ° C. using a mixer. While vacuuming the mixer, 35 parts by weight of rapeseed salad oil (oil phase portion) was added little by little to 65 parts by weight of the aqueous liquid (aqueous phase portion) obtained above, and the mixture was emulsified with stirring to obtain an oil-in-water type preliminary emulsion. . Then, this preliminary emulsion is homogenized at a pressure of 600 k using a high pressure homogenizer (Microfluidizer M-110T type, manufactured by Microfluidex).
An oil-in-water emulsion (mayonnaise-like food) according to the present invention was obtained by homogenization treatment under g / cm ² . In the obtained oil-in-water emulsion, the average particle size of the oil droplet particles was 2.1 μm. Further, its viscosity at 20 ° C. was 50,000 centipoise (cp), and it had a shape retention property required as a mayonnaise-like food. Further, the emulsified product obtained was stored in an atmosphere of 30 ° C. for one week, and the emulsified state (emulsion stability) of the emulsified product was visually observed. The emulsion stability was evaluated by the number of defective products in the following 10 samples. A: 0, B: 1-2, C: 3 or more

[Comparative Example 1] In the same manner as in Example 1 above, an oil-in-water type preliminary emulsion was prepared in the same manner, and then a colloid mill (L type, manufactured by Tokushu Kika Kogyo Co., Ltd.) was used instead of the high pressure homogenizer. An oil-in-water emulsion for comparison (mayonnaise-like food) was obtained in the same manner as in Example 1 except that it was used. The oil-in-water emulsion obtained has an average particle size of 8 oil droplets.
μm. Further, its viscosity at 20 ° C. is 500 centipoise (cp), which is a viscosity for a mayonnaise-like food.
The shape retention was also disqualified.

Example 2 2.22 parts by weight of soy protein powder (Esprogen No. 231, San-ei Chemical Co., Ltd.) instead of 0.46 parts by weight of egg white powder in the above-mentioned Example 1 (dry protein) 2.0 parts by weight of solid content) and 4
An oil-in-water emulsion according to the present invention was obtained in the same manner as in Example 1 except that the aqueous liquid prepared in place of 3.36 parts by weight was used. In the obtained oil-in-water emulsion, the oil droplets had an average particle diameter of 3.0 μm. Further, its viscosity at 20 ° C. was 50,000 centipoise (cp), and it had a shape retention property required as a mayonnaise-like food. The emulsified state of the emulsion obtained after storing the obtained emulsion for one week in an atmosphere of 30 ° C. was examined in the same manner as in Example 1 above.
The above results are summarized in Table 1. The “average particle size” in Table 1 is a measured value on a volume basis. The "viscosity" is a measured value at 20 ° C.

[0022]

[Table 1] Table 1 ──────────────────────────────────── Oil-in-water type water phase / oil phase Dry protein solid average particle size viscosity Emulsion after storage (% by weight) (% by weight) (μm) (cp) Emulsion stability ───────────────────── ──────────────── Example 1 65/35 0.4 2.1 50000 A Comparative Example 1 65/35 0.4 8.0 500 Example 2 65/352 0.0 3.0 50000 A ─────────────────────────────────────

From the results shown in Table 1 above, the oil-in-water emulsions of the present invention (Examples 1 and 2) have high viscosities and good shape retention. The emulsion stability of the emulsion after storage is also good.

[0024]

INDUSTRIAL APPLICABILITY The oil-in-water emulsion of the present invention is extremely stable, with almost no change in the emulsified state even when stored at high temperature for a long time. Further, it has a relatively high viscosity without using a thickener and has a good shape retention property. Further, compared with the emulsion of JP-A-6-54662, the decrease in the flavor is relatively small in spite of the decrease in the protein content.

Claims (2)

[Claims] 1. 90-40% by weight aqueous phase, 10-60
An oil-in-water emulsion comprising a weight% of an oil phase, wherein the water phase is separated from 0.3 to 3% by weight of solid protein in terms of egg protein, soybean protein, milk protein and these proteins. Oil droplets containing at least one protein selected from the group consisting of a single protein and emulsified and dispersed in the aqueous phase are 1.0 to
An oil-in-water emulsion having an average particle size of 4 μm. 2. The oil-in-water emulsion according to claim 1, which is a mayonnaise-like food.